Drill

Abstract

The invention relates to a drill comprising a drill tip, wherein the drill tip comprises at least one main cutting edge having a cutting corner, from which the main cutting edge extends to a center, wherein the drill tip comprises at least one additional cutting edge having an additional cutting corner, from which the additional cutting edge extends in the direction of the center, wherein the additional cutting edge is formed only on an outer portion of the drill tip and is thus shorter than the main cutting edge, wherein the additional cutting corner projects beyond the cutting corner.

The invention claimed is: 
     
       1. A drill comprising a drill tip,
 wherein the drill tip comprises at least one main cutting edge having a cutting corner, from which the main cutting edge extends to a center, 
 wherein the drill tip comprises at least one additional cutting edge having an additional cutting corner, from which the additional cutting edge extends in the direction of the center, 
 wherein the additional cutting edge is formed only on an outer portion of the drill tip and is thus shorter than the main cutting edge, 
 wherein the additional cutting corner projects beyond the cutting corner, and 
 wherein the main cutting edge is directly adjoined by a free surface which slopes downward in the direction of the additional cutting corner and transitions into a secondary free surface which slopes upward in the direction of the additional cutting corner. 
 
     
     
       2. The drill according to  claim 1 , wherein the additional cutting corner projects beyond the cutting corner in an axial direction (A). 
     
     
       3. The drill according to  claim 1 , wherein the additional cutting corner projects beyond the cutting corner in a radial direction (R). 
     
     
       4. The drill according to  claim 1 , wherein the additional cutting corner is rounded. 
     
     
       5. The drill according to  claim 1 , wherein the additional cutting corner is pointed. 
     
     
       6. The drill according to  claim 1 , wherein the cutting corner and the additional cutting corner are configured to have the same shape. 
     
     
       7. The drill according to  claim 1 , wherein the cutting corner and the additional cutting corner enclose an angle (W) that is less than 90°. 
     
     
       8. The drill according to  claim 1 , wherein said drill comprises a plurality of main cutting edges, each of which has a cutting corner that is respectively followed by an additional cutting corner which encloses an angle (W) with the cutting corner, so that a plurality of angles (W) are formed,
 wherein said angles (W) have different sizes. 
 
     
     
       9. The drill according to  claim 1 , wherein said drill comprises a flute, which precedes the additional cutting corner, for receiving chips on the additional cutting corner. 
     
     
       10. The drill according to  claim 1 , wherein the additional cutting edge ends toward the center at a secondary free surface. 
     
     
       11. The drill according to  claim 1 , wherein said drill comprises exactly two main cutting edges, each of which has a cutting corner that is respectively followed by exactly one additional cutting corner.